This study will evaluate the effects of a psychosocial intervention in post-MI patients, who are depressed or have low social support on a combined endpoint of mortality and re-infarction (compared to usual medical care). This study will also: a) to evaluate the effect of the intervention on secondary medical and psychosocial endpoints; b) to evalute the effect of subgroups defined by gender, minority status, and etiology of psychosocial risk (to the extent possible given limited statistical power); c) to conduct exploratory studies of behavioral and physiologic mechanisms.